A. Field of the Invention
This invention relates to novel acrylic fibers having good basic dyeability characteristics.
B. Description of the Prior Art
In general, the basic dyeability characteristics of acrylic fibers are less than desirable. It is known that the basic dyeability characteristics of certain acrylic fibers (e.g. fibers composed of the copolymer of acrylonitrile and vinyl acetate) can be improved by modifying the polymer from which the fibers are prepared to contain basic dye receptive groups (e.g. sulfonate groups) as an integral part of its polymeric structure. The modification is conveniently accomplished by preparing the acrylic polymer in the presence of a sulfonated monomer which is polymerizable with the acrylic polymer-forming monomers. However, the basic dyeability characteristics of certain other acrylic fibers (e.g. fibers of the copolymer of acrylonitrile and vinyl bromide) is not sufficiently improved by the foregoing modification.